[iotdb] 01/03: add doc

[ha...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

haonan pushed a commit to branch fix_mem_control_211
in repository https://gitbox.apache.org/repos/asf/iotdb.git

commit 09eb962c047e9afcf481999d1b5ca3732934b239
Author: qiaojialin <64...@qq.com>
AuthorDate: Fri Nov 6 15:16:17 2020 +0800

    add doc
---
 .../db/engine/storagegroup/StorageGroupInfo.java   |  5 ++--
 .../engine/storagegroup/TsFileProcessorInfo.java   |  4 +++-
 .../org/apache/iotdb/db/rescon/SystemInfo.java     | 28 ++++++++++++----------
 3 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupInfo.java b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupInfo.java
index 57de6eb..e696a60 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupInfo.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupInfo.java
@@ -33,7 +33,8 @@ public class StorageGroupInfo {
   private StorageGroupProcessor storageGroupProcessor;
 
   /**
-   * The total Storage group memory cost
+   * The total Storage group memory cost,
+   * including unsealed TsFileResource, ChunkMetadata, WAL, primitive arrays and TEXT values
    */
   private AtomicLong memoryCost;
 
@@ -76,7 +77,7 @@ public class StorageGroupInfo {
     memoryCost.getAndAdd(-cost);
   }
 
-  public long getSgMemCost() {
+  public long getMemCost() {
     return memoryCost.get();
   }
 
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/TsFileProcessorInfo.java b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/TsFileProcessorInfo.java
index 52bc863..417168e 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/TsFileProcessorInfo.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/TsFileProcessorInfo.java
@@ -30,7 +30,9 @@ public class TsFileProcessorInfo {
    */
   private StorageGroupInfo storageGroupInfo;
 
-  // unsealed TsFileResource, ChunkMetadata, WAL
+  /**
+   * memory occupation of unsealed TsFileResource, ChunkMetadata, WAL
+   */
   private long memCost;
 
 
diff --git a/server/src/main/java/org/apache/iotdb/db/rescon/SystemInfo.java b/server/src/main/java/org/apache/iotdb/db/rescon/SystemInfo.java
index fa1715e..aa32467 100644
--- a/server/src/main/java/org/apache/iotdb/db/rescon/SystemInfo.java
+++ b/server/src/main/java/org/apache/iotdb/db/rescon/SystemInfo.java
@@ -54,17 +54,19 @@ public class SystemInfo {
    * @param storageGroupInfo storage group
    */
   public void reportStorageGroupStatus(StorageGroupInfo storageGroupInfo) {
-    long delta = storageGroupInfo.getSgMemCost() -
+    long delta = storageGroupInfo.getMemCost() -
         reportedSgMemCostMap.getOrDefault(storageGroupInfo, 0L);
     totalSgMemCost.addAndGet(delta);
-    logger.debug("Report Storage Group Status to the system. "
+    if (logger.isDebugEnabled()) {
+      logger.debug("Report Storage Group Status to the system. "
           + "After adding {}, current sg mem cost is {}.", delta, totalSgMemCost);
-    reportedSgMemCostMap.put(storageGroupInfo, storageGroupInfo.getSgMemCost());
-    storageGroupInfo.setLastReportedSize(storageGroupInfo.getSgMemCost());
+    }
+    reportedSgMemCostMap.put(storageGroupInfo, storageGroupInfo.getMemCost());
+    storageGroupInfo.setLastReportedSize(storageGroupInfo.getMemCost());
     if (totalSgMemCost.get() >= config.getAllocateMemoryForWrite() * FLUSH_PROPORTION) {
       logger.debug("The total storage group mem costs are too large, call for flushing. "
           + "Current sg cost is {}", totalSgMemCost);
-      flush();
+      chooseTSPToMarkFlush();
     }
     if (totalSgMemCost.get() >= config.getAllocateMemoryForWrite() * REJECT_PROPORTION) {
       logger.info("Change system to reject status...");
@@ -81,10 +83,10 @@ public class SystemInfo {
   public void resetStorageGroupStatus(StorageGroupInfo storageGroupInfo,
       boolean shouldInvokeFlush) {
     if (reportedSgMemCostMap.containsKey(storageGroupInfo)) {
-      this.totalSgMemCost.addAndGet(storageGroupInfo.getSgMemCost() -
+      this.totalSgMemCost.addAndGet(storageGroupInfo.getMemCost() -
           reportedSgMemCostMap.get(storageGroupInfo));
-      storageGroupInfo.setLastReportedSize(storageGroupInfo.getSgMemCost());
-      reportedSgMemCostMap.put(storageGroupInfo, storageGroupInfo.getSgMemCost());
+      storageGroupInfo.setLastReportedSize(storageGroupInfo.getMemCost());
+      reportedSgMemCostMap.put(storageGroupInfo, storageGroupInfo.getMemCost());
       if (shouldInvokeFlush) {
         checkSystemToInvokeFlush();
       }
@@ -120,11 +122,11 @@ public class SystemInfo {
   }
 
   /**
-   * Flush the tsfileProcessor in SG with the max mem cost. If the queue size of flushing >
-   * threshold, it's identified as flushing is in progress.
+   * Order all tsfileProcessors in system by memory cost of actual data points in memtable.
+   * Mark the top K TSPs as to be flushed,
+   * so that after flushing the K TSPs, the memory cost should be less than FLUSH_THRESHOLD
    */
-  public void flush() {
-
+  private void chooseTSPToMarkFlush() {
     if (FlushManager.getInstance().getNumberOfWorkingTasks() > 0) {
       return;
     }
@@ -144,7 +146,7 @@ public class SystemInfo {
   /**
    * Be Careful!! This method can only be called by flush thread!
    */
-  public void forceAsyncFlush() {
+  private void forceAsyncFlush() {
     List<TsFileProcessor> processors = getTsFileProcessorsToFlush();
     for (TsFileProcessor processor : processors) {
       if (processor != null) {